1. Field of the Invention
The present invention is directed to a novel method for growing Cordyceps sinensis in a substrate and to a novel method for hybridizing different strains of Cordyceps sinensis for the purpose of obtaining strains having the medicinal, health stimulating properties comparable or improved relative to strains of Cordyceps sinensis grown in the wild.
2. Brief Description of Background Art
Cordyceps sinensis is an ascomycetous fungus belonging to the Clavicipitaceae family. In nature Cordyceps sinensis colonizes and lives as a parasite on lepidopterous larvae. Cordyceps sinensis is normally found in the wild in the interior of China, Nepal, Tibet and in the Himalayas in an elevation range of approximately 2,000 to 6,000 meters.
Cordyceps sinensis has been known for a long time in the folk medicine of the Far East, mainly China and Japan, where it is respectively known as “Dong Chong Xia Cao” and “Tochukaso”. In these countries the fungus, usually together with the caterpillar that it colonizes, is included in various soups for treating such diverse conditions as kidney and lung ailments and as a Yin/Yang (sexual) stimulator. Other species of the Cordyceps genus are also known to produce substances usable as antibiotics, immune stimulants, antiviral and antitumor agents.
Since approximately 1950 the worldwide demand for Cordyceps sinensis, to be used as a health stimulant, has grown substantially and attempts have been made to artificially cultivate it and other Cordyceps species as well. By the present the wild stocks of Cordyceps sinensis have been overharvested. To supply the increased worldwide demand in the neutraceutical and pharmaceutical markets varieties of Cordyceps sinensis products have been made available in wide ranging and often questionable purity and quality. Even counterfeit products have been produced to supply the increasing demand.
Until the present investigation and discovery there was no universally accepted method of identifying the substances in Cordyceps sinensis which are responsible for its health benefiting effects, nor was there a standard method of measuring the quantity of one or more of these substances. It was also observed in the prior art and also in investigations made in connection with the present invention that various strains of Cordyceps sinensis provide or include the desired medicinal substances in varying amounts. Further, it was found in the investigation made in connection with the present invention that some commercially available nutraceutical products purportedly comprising Cordyceps sinensis contained none or only very little of the substances characteristic of a true Cordyceps sinensis sample.
In light of the foregoing there is a need in the nutraceutical and/or pharmaceutical arts for a standard method for establishing that a product indeed contains Cordyceps sinensis, for measuring the quantity of Cordyceps sinensis in that product, for developing strains of Cordyceps sinensis that produce the beneficial substances in substantial quantity, and for methods of growing Cordyceps sinensis in substantial quantities on a substrate. The present invention provides methods which satisfy these needs.